Speth will maintain his relationship with the Tata Motors-owned firm by taking up the role of non-executive vice chairman, N Chandrasekaran, Chairman of Tata Sons, Tata Motors and Jaguar Land Rover, said in a regulatory filing.
Speth will also remain on the board of Tata Sons, he added.
"Professor Sir Ralf Speth has decided to retire from his current role as Executive Director and Chief Executive Officer of JLR at the end of his contract term in September 2020," as per the filing.
"I want to thank Ralf for his passion and commitment over the last 10 years. Ralf developed Jaguar Land Rover from a niche UK centric manufacturer to a respected, technological leading, global premium company," Chandrasekaran said.
"A search committee has been formed which will work with me to identify a suitable successor in the coming months," he said.
"Personally, I am looking forward to new and exciting challenges," Speth said.
The shares of Tata Motors were trading at Rs 189.00 apiece on BSE, up 0.51 per cent from the previous close. SID SID ANS ANS